DE2234154A1 - MANIPULATOR - Google Patents

Description

13.087 / 8 40 / egg

ii * · - S "I

Company ASAHI KOGAKU, KOGYO KABUSHIKI KAISHA, Tokyo / Japan

manipulator

The invention relates to a manipulator.

Manipulators are used for very precise adjustment of the mask drying plates or the masked documents in printing devices for the manufacture of integrated semiconductor circuits used. -,

With conventional manipulators, the Mask plates or the masked documents mechanically. A typical example of such a manipulator is the so-called pantograph or cranesbill, which is equipped with parallel legs. The disadvantage of such a

209885/08 9 5

SlrSi -. *> - ■ r 'ι -'ψ "JA Up Λ;'-V'S

The mechanical system is explained in more detail below with the aid of a cranesbill and with reference to FIG.

It is assumed in FIG. 1 that a point P is firmly fixed. The movement of points Q and 0, which are located on a straight line that runs through point P, is considered. If point 0 ^{moves to O 1} , point Q moves to Q ¹ and points O ₁ and O ₂ move to O'.j and O'g, respectively. Since a parallelogram is formed in the system by four straight lines, the segments 00p and O ₁ O, and also O'O'g and O '^ OU, are parallel to one another.

₂ Ρ = 4- ο ₃ <

0 · 0 · ₂ 0O ₂ QO ₁

0 ' ₂ PO ₂ PO ₁ P

holds, AP0'0 ^f _{2 is} similar to ÄPQ'O ^. As a result, the points P, Q and 0 are always on the same straight line. It is known that for this reason the points Q and 0 describe similar curves when they move about the pivot point P, the similarity ratio of which is the same

2 0 9 H Ii 5/0895

PO ₂

is. In mechanical manipulators, the value of the distance POp "is limited, so that the value of the similarity ratio Y * is usually between 100 and 150. Dry masks and masked documents must be set with an accuracy that must be less than 1 / µm OQ ¹ in FIG. 1 is extremely small, which leads to an unsatisfactory result.If the similarity ratio is set between 1000 and 1500 and a setting smaller than 1 μm is to be made, then the above-mentioned movement Ό0 ¹ aus s er is quite large , unless a makeshift adjustment of the drying plates or masked documents in a range of a few / .mu.m is made, and an unsatisfactory result is obtained again. to make.

The operator of a mechanical manipulator is in close proximity of the drying plates and masked substrates, so that it is impossible to the influence of dust and other unwanted foreign particles that come from clothes, the skin, hair, etc. of the operator on which

2098 8 5 / 0-8

Avoid accuracy, yield, cost, and performance of the end product. In order to support the accuracy of a visual setting, it is generally necessary to maintain a constant temperature of approximately 20 ^° C. in order to prevent expansions or contractions.

The operator is responsible for the visual adjustment of the dry masks and the masked documents carried out in safety light, the one for drying plates, and underlay wafers is permitted, which are provided with a cover layer. Red light is used as a safety light in photographic Working and yellow light used when working with covered pads. The operator's eyes are heavily used by these operating conditions.

With "a cranesbill, adjustment can be made in the XY direction of a plane. For rotation through an angle θ, it is necessary to provide, for example, a screw and a nut or a worm thread and a worm wheel, each of these devices having both a Coarse as well as fine adjustment must be equipped, since the adjustment system in the XY direction is completely different from the adjustment system in the θ direction and so is the type of coarse adjustment

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is completely different from that of fine tuning it is impossible to make adjustment in the X-Y and 0 directions at the same time. Also is the setting of a mechanical manipulator is difficult to use and takes a lot of time.

The task is to build a manipulator in such a way that that it can be operated with high accuracy and ease of use both in the X-Y direction of a plane and in the 0 direction of rotation can be actuated and in which the above-mentioned disadvantages of a mechanical manipulator are not

appear.

According to the invention, this object is achieved in that at least one light source and at least one light receiver it is provided that an optical filter is arranged in the light path between a light source and a light receiver that changes its degree of absorption or its degree of reflection continuously or gradually and with the the amount of light hitting the light receiver continuously or can be changed in stages so that the output signal of the light receiver can be converted into pulses, whose Frequency proportional to the size of the output signal is and with which a speed control of a servomotor can be carried out continuously, and that a Differentiation of the direction of movement is to be made, where-

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to a permanent magnet and a switch or a light source, a light receiver and an optical filter that changes its degree of absorption or reflection by leaps and bounds, are provided.

The manipulator according to the invention uses an electro-optical one System and a contactless drive system with speed control and with it can be in simpler Adjustments in the X-Y direction as well as in the θ direction of rotation can be carried out with an accuracy, which is less than 0.5 / * a. Because of the speed control, settings can be made very quickly with the manipulator Time can be carried out with high accuracy, even if the relative position of a mask drying plate or a masked pad is far from the target position. The operator also uses it for monitoring a television set, so you can work with remote control, which eliminates the influence of dust and foreign particles originating from the manager and which reduces the effort of the manager.

The manipulator according to the invention is illustrated in the following by a few exemplary embodiments and with reference to FIGS. 2 to 14 explained in more detail by way of example.

Show it:

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FIG. 2 shows the principle of a manipulator according to the invention; .

FIG. 3 shows an X-Y manipulator according to the invention;

Figures 4, 5 and 6 a perspective view and Top views of an embodiment of an X-Y manipulator;

Figures 7, 8 and 9 are a section and views of

above an embodiment of a P manipulator;

Figures 10, 11, 12 and 13 sections, views of

above and perspective views of the essentials Parts of other exemplary embodiments and

FIG. 14 shows the operator in a view from above and the operating mechanism of an X-Y and a θ manipulator and the directions in which the manipulator can be operated by the operator.

For a better overview, a summary of the reference numbers used in the figures is given in front. It means:.

1, 1-1, 1-2, 1-3, 1-4 ... light sources;

2, 2-1, 2-2, 2-3, 2-4 ... filters;

² T ' ² T " ¹ ' ² T" ² ' ² T ** ^' ² T ~ "· Places where the photocurrent

Hull is;

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2 ·, 2 · -1, 2 »-2, 2'-3, 2« -4 ... places where the photocurrent has a certain Takes value A;

2 '», 2» «- 1, 2»' - 2, 2 »'- 3, 2' '- 4 ... places where the

Photocurrent is 10 times the value A;

2-1 ... places where the photocurrent assumes a certain value R;

2-2 ... places where the photocurrent assumes a certain value U;

3, 3 ¹ , 3-1, 3-2, 3-3 »3-4 ... light receiver;

4, 4-1, 4-2, 4-3, 4-4 ... permanent magnets; 5 · .. magnetic shields; 6, 6-1, 6-2, 6-3, 6-4 ... switch;

7 ... current-frequency converter;

7-1 ... current-frequency converter in the X direction; 7-2 ... current-frequency converter in the Y direction;

8 ... directional discriminators;

.8-1 ... directional discriminators in the X direction; 8-2 ... direction discriminators in the Y direction;

9. ·. Drive circuit for the servomotor;

9-1 * .. Drive circuit for the servomotor of the

X direction;
9-2 ... drive circuit for the servomotor of the Y direction;

10 ... servomotor;

2 ü S 8 8 b / Ü 8 9 b

10-1 ... servomotor for the X direction; 10-2 ... servomotor for the Y direction;

11 ... voltage source with constant voltage;

12 ... wave;

13 ... spring;

14, 14 ¹ ... control buttons; 15 ... warehouse;

16, 16 '... microswitch;

17, 17 '... micro switch;

18 ... support for fine adjustment 19, 19 '... control panels; 20 ... operator a ... position with the coordinates (r, u) a ¹ ... position with the coordinates (v ,. w) 0, O ¹ ... working positions

Connection points;

O ₁ . ° 2 , O ₃ , O ₄ , ο ¹ V ⁰ 2 ° 'y 0 * 4 ... P. . · Pivot point; Q. Point on to the leg O ₁ O;

Q ¹ ... point on the leg O ¹ ^ O ¹ ,; X ... direction of movement; Y ... direction of movement.

FIG. 2 shows the principle of the manipulator according to the invention . A light source 1, for example one, is arranged Luminescent diode, an optical filter that is perpendicular to the optical axis and moves in a horizontal direction

2 09888 / 089S

can be, and a light receiver 3, which is attached opposite the light source 1. The filter 2 is arranged between the light source 1 and the light receiver 3 and the arrangement is designed in such a way that apart from the light emitted by the light source 1, no further light falls on the light receiver 3. The device also contains a fixed permanent magnet 4. In addition to the permanent magnet 4, there is a magnetic switch 6 as a guide switch and a magnetic shielding plate 5 is inserted between the permanent magnet 4 and the switch 6, which can also be moved in the horizontal direction. Das.Filter 2 and the magnetic shielding plate 5 are connected to one another in such a way that they cover the same direction at the same distance when they move. A current-frequency converter 7 is also provided, with which the photocurrent of the light receiver 3 is converted into pulses, the frequency of which is proportional to the current intensity of the photocurrent. With a circuit 8 for differentiating directions, the directional sense is determined with the help of the switching on and off of the switch 6. A servomotor 10 in Ai anxiety of signals of the current-frequency converter 7 and the circuit 8 is operated for the direction discrimination by a drive circuit. 9

The light emitted by the light source 1 shines through the filter 2 and falls on the light receiver 3. The filter

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2 is designed so that with a horizontal shift .in the direction of the arrow X from the position 2 'shown in the figure to the position 2 *', the photocurrent of the light receiver 3 changes by a factor of 10.-In the part of the filter 2, which lies between the sections 2 · and 2 «·, the degree of absorption of the filter changes linearly and continuously or uniformly in steps. If the current-frequency converter 7 operates linearly within the required operating range, then the section 2 ^{11 of} the filter 2 corresponds to a pulse number that is 10 times greater than that of section 2 '. If the absorption rate of the filter changes continuously or if there are enough steps in the area that is penetrated by the light that hits the light receiver with a step change in the absorption rate, the number of pulses changes continuously when the filter is shifted. It has already been mentioned that the filter 2 and the magnetic shielding plate 5 are to be moved or displaced to both sides. If the filter is in a position in which either the section 2 ¹ or the section 2 'is between the light source 1 and the light receiver 3, the permanent magnet 4 is shielded by the magnetic shielding plate 5 and the switch 6 remains in its position Position "off". If the "off" signal is fed from the switch 6 to the circuit 8 for the directional differentiation, a logical

2 0-9 8 Hb / .0 8 9-6

Circuit ensures that the photocurrent of the light receiver 3 is converted into pulses and a signal to rotate in one direction or the other is on the drive circuit 9 for the servomotor. You get a signal "On" from the switch 6, the logic circuit prevents the photocurrent of the light receiver 3 is converted into pulses and there is no signal for the direction of rotation at the drive circuit 9 for the servomotor. So that can a directional distinction can be carried out automatically. The drive circuit 9 operates the servomotor 10 when he Pulses from the current-frequency converter 7 and a signal from the circuit 8 for the directional differentiation receives. In An operational manipulator must combine several of the devices just described. Such a manipulator shall be described below.

FIG. 3 shows a manipulator with which an adjustment in the X-Y direction of a plane is possible. It will omit the description of components which have the same reference numerals as in Figure 2 and which are already in context with Figure 2 'were discussed. With a voltage source 11 of constant voltage, the luminosity is the Light source 1 kept constant. A filter 2 and a magnetic shield plate 5 are attached to a shaft 12 and so 'arranged that they are at the same distance can be moved in the same direction. Of the

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Section 2 ^ of the filter 2 is opaque to light. Section 2 can be penetrated by a small amount of light from the light from light source 1 and the amount of light emitted by light source 1 that can penetrate section 2 is just 10 times the amount of light that penetrates section 2 ¹ can. The part of the filter 2 that lies between the sections 2 · and 2 ¹¹ is designed so that its degree of absorption changes continuously or in steps. A spring 13 is arranged so that the position of the center line of the shaft 12 is always at the same distance from The centers of the light receivers 3-1 and 3-2 are located if no external force is acting on the shaft 12. In the state shown in FIG. 3, the photocurrents of the light receivers 3-1 and 3-2 are equal to O ₁ . Since the magnetic field of the permanent magnet 4 is shielded by the magnetic shielding plate 5, the magnetic switches 6-1 and 6-2 are in the "off" position. As a result, the current-frequency converters 7 and the circuit 8 for the directional differentiation do not receive any input signals and the drive circuit 9 for the servomotor does not work.

If the shaft 12 is moved in the direction of the arrow X so far that the section 2 »of the filter 2 is above the Light receiver 3-1 is located, then light from the light source 1 shines through section 2 «, reaches the light em-

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pfanger 3-1 and a photocurrent of a certain size, for example the size A is generated. The section moves on the other side of the arrangement 2φ of the filter from the beam cone of light source 1 so that the light receiver 3-2 is irradiated unhindered by the light from the light source. and generates a photocurrent, which is more than 10 times as large as the photocurrent A obtained with the light receiver 3-1. Simultaneously switch 6-1 is in the "off" position and switch 6-2 is in the "on" position, since the magnetic field of the permanent magnet 4 assigned to it is no longer shielded by the magnetic shielding plate 5 will. The photocurrent of the size A of the light receiver 3-1 and the photocurrent of the light receiver 3-2, which is greater than 1OA are, as input signals at the current-frequency converter 7. An "off" signal of the switch 6-1 and an "on" signal of the switch 6-2 are fed as input signals to the circuit 8 for the directional discrimination. Will be dated Switch 6-2 a "on" signal is fed to the circuit 8 for the directional differentiation, so a logic Circuit causes the photocurrent of the light receiver 3-1, which is arranged on the other side of the shaft 12, is converted into pulses, and that a signal for a rotation, "for example clockwise, is applied to the drive circuit 9 for the servomotor. If an" on "signal from switch 6-1 to circuit 8 for the direction

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Discrimination supplied, it is effected with the logic circuit that the photocurrent of the light receiver 3-2 is converted into pulses and a rotation signal for the counterclockwise direction on the drive circuit 9 for the servomotor. In the case discussed above, in which the switch 6-2 is in the "on" position, therefore a clockwise rotation signal from the directional discriminating circuit 8 to the circuit 9 for the drive of the servomotor and the photo current of the size A of the light receiver 3-1 is with the current frequency converter 7 transformed into pulses that have a frequency proportional to the size A of the photocurrent is. These pulses are also applied to the circuit 9 for driving the servomotor. If the pulse rate is the same P, the servomotor 10 is controlled by the drive circuit 9 driven clockwise at a frequency P.

If the shaft 12 is moved further in the direction of the arrow X so far that the section 2 ^{11 of} the filter 2 is just above the light receiver 3-1, then this light receiver 3-1 generates a photocurrent, the strength of which is 10 times that Photocurrent strength A is obtained when the section 2 · is above the light receiver 3-1. The strength of the photocurrent is then 10A *. At the same time, the photocurrent that is emitted by the light receiver 3-2 does not change and its strength does not change

2 0 9 8 8 B / U 8 9 £

is still bigger than 1OA. The switch 6-1 also remains in the "off" position and the switch 6-2 in the Position "on". The frequency of the pulses emitted by the current-frequency converter 7 is 1OP and the output signal of the direction discrimination circuit 8 still represents clockwise rotation. Therefore, the drive circuit 9 causes the servomotor 10 to rotate clockwise at the pulse frequency 1OP.

It has already been mentioned that the degree of absorption of the part of the filter 2, which lies between the sections 2 'and 2 ¹¹ , is set so that with a corresponding filter ^{setting 1,} the pulse frequency can assume any value between P and 1OP. The speed of rotation of the servomotor 10 can therefore be changed continuously.

To be able to make an adjustment in the X-Y direction, it is necessary to make a distinction between the signs + X, -X, + Y and -Y. "For this purpose, two of the in Figure devices shown arranged perpendicular to each other and operated in parallel by each independent control system ·. Looking at a two-dimensional X-Y coordinate system, which is perpendicular to the central axis of shaft 12, which is equidistant from each of the light receivers, a displacement of the shaft 12 enables a

2 0 ^C J b υ b / 0 8 9 5

separation of the signs + X, -X, + Y and -Y. In addition, with the changed position of the shaft 12 pulse frequencies are obtained for the X and Y directions. The direction of movement of the shaft 12 enables the differentiation of direction and determines the sign of the rotary movement of the servomotors for the X-direction and the Y-direction. The movement, of the shaft 12 generates pulse frequencies for the X-direction and the Y-direction which are proportional to the length of the displacement and thus the rotational speed of the pulse motors for the X-direction and the Y-direction is determined. The pulse motors for the X direction and the Y direction are, for example, equipped with adjusting devices that move exactly in the same direction as the shaft 12 at a speed proportional to the displacement distance of shaft 12 is.

Figures 4a, 4b and 4c show an embodiment of an X-Y manipulator. A rotatable knob 14 is in engagement with a shaft 12 via a bearing 15. Return springs '13 are arranged so that without an attacking external force the central axis of the shaft 12 by a line runs at the same distance from the light receivers 3-1 ,. 3-2, 3-3 and 3-4 is. This line is shown below referred to as the rest position. The shaft 12 does not rotate when the knob 14 is rotated. A right angle The coordinate system is spanned in a plane that

2 0 9.8 8 5/08 9 5

is perpendicular to the central axis of the shaft 12. The origin of the coordinate system lies in the central axis and the coordinate axes as FIG. 4b shows, denoted by + X, -X, + Y and -Y. With a microswitch 16, which is in Button 14 is arranged, a drive circuit 9-1 for a servomotor for the X-direction and a drive circuit 9-2 for a servomotor for the Y-direction can be operated will. This will be discussed in the following. With a microswitch 17, a single current surge or pulse, to a servomotor 10-1 for the X direction or to a servomotor 10-2 for the Y-direction. This pulse is applied for each motor independent of the other motor and enables a drive with a single current surge or pulse. The device according to The figure also has the following components, the same components each having the same characteristics: Luminescent diodes 1-1, 1-2, 1-3 and 1-4; Filters 2-1, 2-2, 2-3 and 2-4; Silicon photodiodes 3-1, 3-2, 3-3 and 3-4 as Light receiver; Permanent magnets 4-1, 4-2, 4-3 and 4-4; Switches 6-1, 6-2, 6-3 and 6-4; a magnetic shield plate 5; a current-to-frequency converter 7-1 for the X direction; a current-to-frequency converter 7-2 for the Y direction; a circuit 8-1 for direction discrimination in the X direction and a circuit 8-2 for direction discrimination in the Y direction. A drive circuit 9-1 for the servomotor for the X direction is dependent on

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speed of input signals "operated by the current-frequency converter 7-1 and the circuit 8-1 for direction discrimination in the X direction. A drive circuit 9-2 for a servomotor in the Y direction becomes operated as a function of input signals, which it from the current-frequency converter 7-2 and the circuit 8-2 for the directional distinction in the Y-direction receives. In addition, a fine adjustment device 18 for Semiconductor wafers or documents, drying plates and masks provided by the servomotor 10-1 for the X direction and the servomotor 10-2 is driven for the Y direction.

The device shown in Figures 4a to 4c can be operated in the following way according to the principle that was described in connection with Figures 2 and 3: If the button 14 is brought into any position of the rectangular coordinate system of the above-mentioned plane, so will correspond to the coordinate values of the central axis of the button 14 a signal for the direction and the speed conveyed the movement to the servomotor 10-1 for the X direction and the servomotor 10-2 for the Y direction.

A detailed description of the mode of operation of the exemplary embodiment discussed is given below in connection with Figure 5 and Figure 6 given. Figure 5 shows the

089b

Filters 2-1, 2-2, 2-3 and 2-4 and the 'light receivers 3-1, 3-2, 3-3 and 3-4. In Figure 6 are the magnetic shield plate 5 and the magnetic switches 6-1, 6-2, 6-3 and 6-4 are shown.

Figures 5a and 6a show a state in which the button 14 of Figure 4 has not been moved. This means that the shaft 12 is in the rest position. A state is shown in FIG. 5b and FIG. 6b in which the button 14 has been moved into a position with the coordinates r, u in the first quadrant of the right-angled coordinate system. The filters 2-1, 2-2, 2-3 and 2-4 are arranged at right angles to one another in order to be able to detect the movement in both the X and Y directions. The degree of absorption of the filter changes, as shown in FIGS. 2 and 3, continuously or in steps. The sections 2-1, 2-2, 2 _T -3 and 2 _T -4 are completely opaque to the light from the light sources 1-1, 1-2, 1-3 and 1-4. The sections 2'-1, 2 · -2, 2'-3 and 2'-4 of the filters can only be penetrated by such a small amount of light that the photocurrent of the corresponding light receiver only has the strength A. The sections 2 "-1, 2"'- 2, 2 "' - 3 and 2"'- 4 of the filters are permeable to an amount of light with which a photocurrent is obtained which is 10 times the photocurrent that is obtained when irradiating the sections 2 »-1, 2'-2, 2'-3, and 2'-4. The strength of this photocurrent is therefore 10A.

2 ü 9 8 8 b / 0 8 9 B

In FIG. 5a, the light receivers are 3-1, 3-2, 3-3 and 3-4 straight from the sections of filters 2-1, 2 ^, - 2, 2rp-3 and 2 "-4 covered, which are not translucent. The photocurrent of each light receiver is therefore zero. In Figure 6a, all switches are 6-1, 6-2, 6-3 and 6-4 because of the shielding by the magnetic shielding plate 5 in the "off" position. Therefore becomes the microswitch 16 is switched on, neither the servomotor 10-1 for the X direction nor the servomotor 10-2 for the Y direction actuated.

If the center of the button 14 is in a position with moves the coordinates (r, u), as shown in FIG. 5b, the photocurrent of the light receiver 3-1 the strength R, the photocurrent of the light receiver 3-2, the strength U and the photocurrents of the light receiver 3-3 and 3-4 have a strength greater than 10A. The photo currents R and U are given by the following relationships limited:

A έ R ^ 1OA, A ^ U ^. 1OA.

The switches 6-1 and 6-2 in Figure 6b are magnetically shielded and accordingly in the "off" position. Since the Magnetic shielding 5 no longer covers the permanent magnets 4-3 and 4-4, the switches 6-3 and 6-4 are

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are no longer shielded from the magnetic field and are therefore in the "on" position. The device is designed so that when the switch 6-3 is in the "on" position, the photocurrent of the light receiver 3-1 is converted into pulses that represent the direction + X (clockwise rotation), and in the "on" position of the switch 6-1 the photocurrent of the light receiver 3-3 is converted into pulses which represent the direction -X (counterclockwise rotation). Further logic circuits are arranged which act in the same way with respect to the light receivers 3-2 and 3-4. In the position with the coordinates (r, u) the switches 6-3 and 6-4 are in the "on" position. The circuit 8-1 for the directional discrimination in the X direction will therefore determine the sign + X and the circuit 8-2 for the directional discrimination in the Y direction will specify the sign + Y. A photocurrent R is converted into pulses by the current-frequency converter 7-1 for the X direction, which is obtained when light _{falls through the section 2 r} -1 of the filter 2-1 onto the light receiver 3-1. The current-frequency converter 1-2. for the Y-direction converts a photocurrent U in pulses by which is obtained when light is the portion of the filter 2-2 and irradiated 2 -2

reaches the light receiver 3-2. If the number of corresponding pulses is R ¹ and U ¹ , then in this state there is between the photocurrents and pulse frequencies

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following relationship:

UU ».
R ~ _t R «.

It is necessary that the servomotor 10-1 for the X direction and the servomotor 10-2 for the Y direction is only actuated when a setting of the masked Make dry plates or the masked semiconductor wafers is. For this reason, a switch 16 shown in Figure 4c is the drive circuit 9-1 for the Servomotor for the X direction and the drive circuit 9-2 upstream for the servomotor for the Y direction. Only if the switch 16 is in the "on" position, the servomotors 10-1 and 10-2 are operated by the associated drive circuit 9-1 and 9-2. Will the microswitch 16 brought into the "on" position, the fine adjustment device 18 moves because of the actuation of the servomotors 10-1 and 10-2 for the X-direction and the Y-direction depending on the coordinates (r, u) of the point a in the direction

9 = tan " ¹ -aiii *"

with speed

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(U ¹ ) ² + (R ') ² (K: constant).

If the button 14 is moved to a point a ¹ with the coordinates (v, w), which is on a straight line through the point a and the origin of the coordinate system, the photocurrent intensity of the light receiver 3-1 is equal to V, where V- is greater than R and the photocurrent strength of the light receiver 3-2 is equal to W, where ¥ is greater than U. The pulse frequencies V ¹ and W ^f , which are obtained in the manner already discussed by the current-frequency conversion, therefore satisfy the following relationships:

UU ¹ V
R "R ¹ W ¹ ,

+ (R ¹ ) ² < kV (ν) ² +

The fine adjustment carrier 18 therefore moves at a greater speed. A switch or button 17 is arranged so that with this switch the servomotors 10-1 and 10-2 for the X-direction and the Y-direction can only be supplied with a current surge or pulse if at least one of the switches 6-1, 6-2, 6-3 and 6-4 is in the "on" position *. If the button 14 is at point a (r, u) or at point a ¹ (v, w), switches 6-3 and 6-4 are located

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in the "on" position. This allows the circuits 8-1 and 8-2 to differentiate the direction for the X direction and determine the signs + X and + Y in the Y direction. Because of the operation of the drive circuits 9-1 and 9-2 for the Servomotors of the X-direction and the Y-direction are then the servomotors 10-1 and 10-2 for the X-direction and the In the Y direction, perform a rotation limited by the current surge with the sign + X or + Y. It follows, that the fine adjustment support 18 is in the direction tanG = 1/1, i.e. moved in the direction θ = 45 ° in the first quadrant.

FIG. 7 shows an exemplary embodiment of a θ manipulator. The operating button 14 of the Θ-Mani- " pulators, microswitches 16 and 17 and a shaft 12, which is on Center of the button 14 is attached. If there is no rotational force acting on the button 14, the shaft 12 is activated by the spring 13 in a fixed position, the so-called rest position, held. A filter changes the light shining through it continuously or gradually if it is rotated. A light source 1 and a light receiver 3 are opposite one another and the filter is at a constant distance between them arranged from the central axis of the shaft 12. In addition, FIG. 7 shows a permanent magnet 4, a magnetic one Shielding plate 5, with which the magnetic field of the permanent magnet 4 is shielded, and a magnetic switch 6. With a voltage source 11 that has a constant voltage

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supplies the light source 1 is fed, which can be, for example, a light-emitting diode. The light of the light source 1 shines through the filter 2 and falls on the light receiver 3. The photocurrent of the light receiver 3 is converted into pulses with a current-frequency converter 7. By the "on" or "off" positions of the switch 6 are determined by a circuit 8 for differentiating the direction of rotation. A corresponding input signal is fed to the drive circuit 9 for the servomotor. The drive circuit 9 for the servomotor drives' the servomotor 10 at a speed and with a direction of rotation that is determined by the pulse frequency of the current-frequency converter 7 generated pulses and the direction signal of the circuit 8 set for the directional differentiation are. A rotatable carrier 18 is moved with the servomotor 10. It is necessary that the carrier 18 only Can be rotated when setting a masked dry plate or underlay or a masked semiconductor wafer is to take place. Therefore, the drive circuit 9 for the servomotor is a switch upstream so that only in the "on" position of the switch 16, the servomotor 10 of the drive circuit 9 for the servomotor can be operated. In addition, a switch or button 17 is provided, which in its "on" position only impresses a current surge or a pulse on the servomotor 10. The direction of rotation of the rotation is determined by the switching

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Circle 8 is set for the differentiation of direction.

In the device just described, the pulse frequency obtained by rotating the knob 14 around his Receives center point and the signal that represents the direction of rotation is fed to the servomotor 10 and one receives a Movement sequence that is related to the principle that is related to Figure 2 was discussed, corresponds.

FIG. 8 shows the relative position of a filter 2 which can be rotated in the direction of the arrow about the shaft 12 of a 0-manipulator. A fixed light receiver 3 is also shown. The section 2 _{T of} the filter 2 is opaque. The section 2 'is only permeable to such a small amount of light that the photocurrent of the light receiver 3 only has the strength A. The section 2 'can be irradiated with such a large amount of light that the photocurrent obtained is 10 times the photocurrent obtained when the section 2 is irradiated. The strength of this photocurrent is therefore 10A. The photocurrents that are obtained when the filter sections are irradiated between the section 2 "and the section 2" change continuously from a photocurrent strength A to a photocurrent strength of 10A when the filter is rotated. Converter 7 generates a pulse frequency P ¹ , so with the arrangement any im-

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pulse frequency can be obtained, which is between P ¹ and 1OP ¹ '. It is thus possible to control the number of pulses per unit of time which are fed to the servomotor 10, and the rotational speed of the servomotor 10 is to be controlled accordingly.

FIG. 9 shows relative positions of the magnetic shielding plate with respect to a switch 6. Located in FIG. 9a the button 14 is in its rest position and the position of the switch 6 is "off". In Figure 9b the knob 14 is rotated in the direction of the arrow X. The switch 6 is thus in its "on" position, which means the direction of rotation 'can easily be determined.

FIG. 10 shows the essential part of another exemplary embodiment. A filter 2 reflects the light from a fixed light source 1. If the filter 2 is moved, so the amount of reflected light changes continuously or gradually. A light receiver 3 is in the light path of the reflected light arranged so that its photosensitive surface is at right angles with the optical Forms the axis of the reflected light. As a result, the photocurrent of the light receiver 3 increases continuously or approximately continuously changes. After a current-frequency conversion of the photocurrent, operating

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steps corresponding to that discussed in connection with FIG. 2 ″ Principle to be carried out.

In each of the embodiments shown in Figures 11 and 12, there is a light emitting diode, for example a light emitting diode 1, a light receiver 3 and a filter 2 are arranged. The amount of the filter 2 translucent or light reflected from the filter 2 suddenly changes very greatly and by means of the sudden difference in the strength of the photocurrent of the light receiver 3 can be an "on-off" signal for determining the sign the direction of movement or the sense of rotation can be obtained.

The. Figures 13a, 13b and 13 ° show details of the optical filter mentioned above. Figure 13a shows a

Filter, which is a photographic dry plate or photographic film. In the figure, the filter is arranged between a light-emitting diode and a light receiver 3. Moves the light emitting diode 1 and the. Light receiver 3 from position 3 to position 3 ¹ relative to filter 2, ie in direction X, the amount of transmitted light increases by a factor of 10. When moving in direction Y, the amount of transmitted light remains constant. A diagram shows the relationship between the position in the X direction relative

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to filter 2 and the associated current intensity of the light receiver. It can be seen from the diagram that the photocurrent strength is proportional to the position in the X-direction. The transmission density of a photographic film or a photographic drying place is given by the decadic logarithm of the reciprocal value of the degree of transmission T: log _1Q 1 / T. It is difficult to change the density of the filter continuously or in steps in such a way that proportionality is obtained between the relative position in the X direction of the filter and the corresponding photocurrent strength of the light receiver, as shown in the diagram in FIG. 13a. To remedy this, a light receiver with a larger light-sensitive surface and the following filter arrangement can be used: FIG. 13b shows that the width of the black and white stripes is changed in order to change the effective light transmission in the X direction. With such a filter, it is very easy to maintain proportionality between the relative position in the X direction of the filter and the corresponding photocurrent strength of the light receiver. In addition, the characteristics of the filter can be made uniform. Figure ^13c shows a filter that is made in the following way: A hard chrome coating is placed on a glass plate and this chrome coating is light! sensitive layer. After exposure and development of the light-sensitive layer, the chrome

20988S / Ü895

layer etched and after this operation you already get the finished filter. In the figure, the dashed r th surfaces the chrome strips, whereby the entire chrome layer was vapor-deposited. The pattern has the same configuration like that of Figure 13 *> Proportionality between the relative position in the X-direction of the filter and the photocurrent is guaranteed, the photocurrent being through the light the light source is obtained, which is reflected by the filter and hits the light receiver. In the Y direction the photocurrent remains unchanged.

FIG. 14 shows the operation of a manipulator according to the invention. The drawing shows control panels 19 and 19 'for an X-Y and a θ manipulator. Microswitch 16 and 16 · are arranged with which the servomotors can be switched on for the period of time that is required for setting the masked drying plate and the masked base are required. In addition, microswitches 17 and 17 'are provided, in order to be able to supply the servomotors only with a current surge or an impulse. "The operator 20 moves with his right hand the button 14 of the X-Y manipulator in an arbitrary position in the direction of the arrows and switches the microswitch 16j ^ in to a setting of the masked dry plate or the masked base in the X-Y plane. MJLt turns his left hand the operator 20 also presses the button 14 of the Θ-Mani-

2 0 Β 8 8 b / ü 8 9 b

pulators in the directions of the arrows and turns on the microswitch 16 · when there is a setting of the masked Troekenplatte or the masked base wants to perform in the θ direction of rotation. It is therefore possible carry out the work steps with both hands at the same time.

In a conventional mechanical manipulator, an adjustment of the masked dry plate or the masked Underlay not possible with a reduced movement of the manipulator button. For this reason it was very precise adjustment of a masked dry plate or a masked base practically impossible and from mechanical For reasons it was very difficult to make an adjustment when there were long distances between successive Positions of the masked drying plate or the masked base were to be overcome. Also is in the case of mechanical manipulators, the mechanism for setting in the X-Y direction is completely different from the mechanism for adjustment in the θ direction and the coarse and fine adjustment methods are also complete different. Mechanical manipulators. Therefore have the disadvantage of a complicated operation and require a lot. Time for an adjustment. With the inventive Manipulator, the disadvantages of mechanical manipulators are overcome by the fact that a speed

20988h / U89b

control of the servomotor with an electro-optical System is carried out. With the manipulator according to the invention, a setting with high accuracy, the lower than 0.5 / µm can be obtained and at this setting the movement of the button of the manipulator can be small, making a scaled-down embodiment with light weight can be used.

In addition, the manipulator according to the invention controls the speed of the servomotor so that a fine adjustment can be obtained in a short time even if the successive relative positions of the masked drying plate or the masked base are far apart. Because of the electro-optical system, the operator can work remotely. Therefore, with a surveillance television camera, the influence of dust originating from the operator can be avoided and the operator's strain is reduced. It should be emphasized that the manipulator according to the invention can be used not only for the production of integrated circuits but also for setting microscopes, projectors, measuring instruments, etc., whereby the advantages of remote control are retained, which are that harmful influences by the operator are eliminated are. It is also possible to use DC motors of different types instead of a motor operated with current pulses.

209885/0896

Claims (2)

Patent (protection) claims Manipulator, characterized in that at least one light source (1) and at least one light receiver (3) it is provided that in the light path between a light source and a light receiver an optical Filter (2) is arranged that its degree of absorption or its degree of reflection continuously or in stages changes and with which the amount of light hitting the light receiver continuously or in steps it can be changed that the output signal of the light receiver can be converted into pulses, the frequency of which is proportional to the size of the output signal and with which a speed control of a servomotor (10) can be carried out continuously, and that a distinction the direction of movement is to be made, including a permanent magnet (4) and a switch (6) or a Light source (1, Fig. 11, Fig. 12), a light receiver (3, Fig. 11, Fig. 12) and an optical filter (2, Fig. 11, Fig. 12 ^ that its degree of absorption or reflection changes by leaps and bounds are provided. 2. Manipulator according to claim 1, characterized gekennzeicznet, that with remote control via a surveillance television camera, a highly accurate setting in the shortest possible time 209885/0895 even if there is a large discrepancy between two consecutive ones Positions is feasible. 2 0 9i b 8. b / ü 8 9 5 Lee r side